The influence of kynurenine, neopterin, and norepinephrine on tubular epithelial cells and alveolar fibroblasts

Abstract

We have examined the effect of kynurenine, neopterin and norepinephrine on epithelial cells and fibroblasts: the total DNA synthesis (by adding 3H-thymidine), the mitotic index, the amount of pathological mitosis and apoptosis. We have observed that kynurenine, neopterin and norepinephrine induce pathological mitosis and apoptosis of epithelial cells of kidney. The total DNA synthesis increases by the incubation of the epithelial cells with neopterin and norepinephrine. We have found an increase of pathological mitosis after addition of kynurenine, neopterin and norepinephrine to fibroblast cell culture. The total DNA synthesis is promoted by neopterin and norepinephrine, while kynurenine does not alter it. These data allow us to suggest that kynurenine, neopterin and norepinephrine promote epithelial cell damage leading to cell death through apoptosis, and can therefore be added to the factors, which promote the pathological mitosis of fibroblasts.